Menopause emerges as a clue in women’s Alzheimer’s risk

Women represent nearly two-thirds of Alzheimer’s diagnoses, and at age 65 their remaining lifetime odds are 1 in 5. Researchers say women’s slightly longer lifespan cannot fully account for the disparity. Instead, biological traits such as hormones and chromosomes may influence susceptibility to chronic conditions. The inequity extends beyond sex: Black Americans experience Alzheimer’s at double the rate of non-Hispanic white Americans.

Menopause is a major focus of the research. Alzheimer’s-related changes may start about 20 years ahead of diagnosis, which commonly happens between 72 to 75. Counting backward brings that process close to 51, the typical age for menopause. Estrogen helps fuel brain cells, maintain neural connections and protect regions involved in attention, planning and recall.

Lisa Mosconi’s imaging research found 30% less brain energy in participants going through or beyond menopause. Similarly aged male participants showed little change or none. Estrogen manages as much as 25% of glucose use in a woman’s brain, so declining levels may help explain forgetfulness and mental fog during perimenopause. Prolonged fuel shortages may cause the brain to tap white matter for energy. Menopause may also raise the likelihood of amyloid buildup among women already predisposed to Alzheimer’s, although plaques do not always result in dementia.